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1.
Environ Pollut ; 298: 118849, 2022 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-35032602

RESUMEN

Globally, sea turtles are at high risk of ingesting plastic. However, research on plastic ingestion by sea turtles in East Asia is scant, and no quantitative or qualitative investigation has been conducted in Korean waters. This study examined the plastic ingestion of sea turtles stranded, floating, or incidentally captured in Korean waters between 2012 and 2018. The quantity, shape, color, size, polymer type, and original usage of plastic debris (>1 mm) ingested by sea turtles were analyzed after being sorted from the gastrointestinal tracts of 34 turtles (21 loggerheads (Caretta caretta), 9 green turtles (Chelonia mydas), 2 leatherbacks (Dermochelys coriacea), and 2 olive ridleys (Lepidochelys olivacea)). The ingestion frequencies of greens, loggerheads, olive ridleys, and leatherbacks were 100%, 81%, 50%, and 50%, respectively. The mean amount of plastic ingested was 108 ± 253 mg/kg (38 ± 61 n/ind.). The ingested debris tended to be films and fibers (>80%), light in color (white and transparent; 65%), and light polymers (polyethylene, polypropylene, polypropylene [poly (ethylene:propylene)], expanded polystyrene; 93%). The original uses were identified for 187 pieces; single-use plastics (e.g., plastic bag and packaging) and fishing and aquaculture items (e.g., twine and net) were found to dominate. Green turtles (264 ± 433 mg/kg) ingested significantly higher amounts of plastic than loggerheads (72.8 ± 156 mg/kg). Green turtles ingested mostly fibers (51%), such as rope, twine, and net, while loggerheads ingested largely films (61%), such as plastic bags and packaging. Interspecies differences in quantities and shapes of ingested debris may be related to their distinct feeding habits and geographical range of movement. The present study demonstrates that sea turtles foraging in Korean waters are considerably affected by marine plastic debris, and indicates that proper waste management of single-use plastics and fishing gears is urgently needed to mitigate the damage that plastic debris causes to marine wildlife.


Asunto(s)
Tortugas , Contaminantes del Agua , Animales , Ingestión de Alimentos , Plásticos , Polímeros , República de Corea , Contaminantes del Agua/análisis
2.
Korean J Parasitol ; 58(3): 279-285, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32615741

RESUMEN

We intended to describe 2 digenean trematodes found from a Chinese sea snake, Laticauda semifasciata, as the new fauna in the Republic of Korea. The snake was caught offshore of Aewol-eup, Jeju-do, in August 2017. Two species of fluke were found in the lung and intestinal tract of the snake in the process of necropsy. They were identified as Pulmovermis cyanovitellosus Coil and Kuntz, 1960 and Harmotrema laticaudae Yamaguti, 1933, respectively based on the morphological characters. Pulmovermis cyanovitellosus showed elongated body with well-developed and elongated male genital system and compact vitelline. And H. laticaudae was characterized by linguiform body with heavily armed cirrus with excretory system. This is the first time both species have been reported and described off the Korean coast. We provide morphological descriptions with some comments on their biology and geographical distribution. In addition, the taxonomic validity of the genus Hydrophitrema Sandars, 1960 was discussed, in terms of morphological descriptions and host ranges. This study provides novel insight into digenean fluke species existing off the coast of Korea.


Asunto(s)
Laticauda/parasitología , Trematodos/aislamiento & purificación , Animales , República de Corea , Trematodos/anatomía & histología
3.
Yonsei Med J ; 60(8): 713-719, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31347325

RESUMEN

PURPOSE: We aimed to evaluate the clinical significance of a disintegrin and metalloproteinase 8 (ADAM 8) as a potential blood biomarker for gastric cancer (GC). MATERIALS AND METHODS: Blood ADAM 8 was measured by ELISA. Cytokines/chemokines [interleukin-23 (IL-23), stromal cell-derived factor 1α/CXC chemokine ligand 12 (SDF-1α/CXCL12), interleukin-8 (IL-8), and soluble CD40 ligand (sCD40L)] were measured by chemiluminescent immunoassay. They were compared among five groups; normal/gastritis, high-risk, early GC (EGC), advanced GC (AGC) without distant metastasis, and AGC with distant metastasis by one-way analysis of variance in both training (n=80) and validation dataset (n=241). Clinicopathological features of GC and GC-associated cytokines were evaluated for their correlations with blood ADAM 8. To evaluate the diagnostic accuracy to predict GC, receiver operating characteristic (ROC) curve and logistic regression were used. RESULTS: Blood ADAM 8 significantly increased along GC carcinogenesis in both training (ANOVA, p<0.001) and validation dataset (p<0.001). It was significantly higher in EGC compared to high-risk (post-hoc Bonferroni, p=0.041) and normal (p<0.001). It was also higher in AGC compared with high-risk (p<0.001) and normal (p<0.001) groups. However, no significant difference was found between cancer groups. Blood ADAM 8 was correlated with N-stage (Spearman's correlation, γs=0.320, p=0.011), but not with T-stage or M-stage. Pearson's correlations showed blood ADAM 8 was closely correlated with pre-inflammatory cytokines, IL-23 (p=0.036) and SDF-1α/CXCL12 (p=0.037); however, it was not correlated with pro-angiogenic cytokine IL-8 (p=0.313), and sCD40L (p=0.702). ROC curve and logistic regression demonstrated that blood ADAM 8 showed higher diagnostic accuracy (sensitivity, 73.7%; specificity, 86.2%) than CEA (sensitivity, 23.1%; specificity, 91.4%). Combination of ADAM 8 and CEA further increased the diagnostic accuracy to predict GC (sensitivity, 81.8%; specificity, 84.0%). CONCLUSION: Blood ADAM 8 is a promising biomarker for early detection of GC.


Asunto(s)
Proteínas ADAM/sangre , Biomarcadores de Tumor/sangre , Detección Precoz del Cáncer , Proteínas de la Membrana/sangre , Neoplasias Gástricas/sangre , Neoplasias Gástricas/diagnóstico , Área Bajo la Curva , Antígeno Carcinoembrionario/sangre , Citocinas/sangre , Femenino , Humanos , Modelos Logísticos , Masculino , Estadificación de Neoplasias , Curva ROC , Reproducibilidad de los Resultados , Neoplasias Gástricas/patología
4.
J Wildl Dis ; 53(4): 749-760, 2017 10.
Artículo en Inglés | MEDLINE | ID: mdl-28700322

RESUMEN

A total of 600 wild birds were analyzed for the causes of mortality in the Republic of Korea (ROK) from 2011 to 2013. Avian poxvirus (APV) infections were identified as the primary cause of mortality in 39% (29/74) Oriental Turtle Doves (Streptopelia orientalis). At necropsy, all 29 S. orientalis birds, of which, 76% (22/29) were juveniles, had severe diphtheritic lesions in their oral and nasal cavities and on their eyelids, which were the lesions of APV that resulted in mortality. We detected APV infection by chorioallantoic membrane inoculation and molecular study of the partial region of the P4b gene. All isolates belonged to the same APV strain and were identical to strains isolated from several different pigeon species in South Africa. Phylogenetically, the APV strain identified in S. orientalis belonged to subclade A2, which includes isolates from several species of pigeons from different parts of the world, including the United Kingdom, Germany, India, Egypt, Hawaii, Georgia, Hungary, South Africa, Tanzania, and the ROK. This identity indicated that this diphtheritic APV strain may be a potential pathogen of other pigeon species in the ROK and neighboring countries throughout the range of S. orientalis. However, reticuloendotheliosis virus insertion into the APV genome was not detected by PCR in any of the 29 APV infections. An identical strain of APV observed in S. orientalis was also detected in Culicoides arakawae (biting midge), with annual peak populations corresponding to the presence of APV in S. orientalis. Culicoides arakawae may be a primary vector of APV in S. orientalis. Active surveillance of APVs in wild birds and C. arakawae is needed to better understand the epidemiology of APVs, host-vector relationships, and its ecological effects on S. orientalis in the ROK.


Asunto(s)
Avipoxvirus/aislamiento & purificación , Enfermedades de las Aves/epidemiología , Ceratopogonidae/virología , Columbidae , Insectos Vectores/virología , Infecciones por Poxviridae/veterinaria , Animales , Avipoxvirus/clasificación , Avipoxvirus/genética , Enfermedades de las Aves/patología , Enfermedades de las Aves/transmisión , Enfermedades de las Aves/virología , Columbidae/parasitología , Columbidae/virología , ADN Viral/química , ADN Viral/aislamiento & purificación , Femenino , Filogenia , Reacción en Cadena de la Polimerasa/veterinaria , Infecciones por Poxviridae/epidemiología , Infecciones por Poxviridae/patología , Infecciones por Poxviridae/transmisión , República de Corea/epidemiología
5.
J Food Sci ; 82(1): 36-43, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27883364

RESUMEN

The objectives of the current study were to determine S-methyl-L-methionine (SMM) from various Brassicaceae family vegetables by using validated analytical method and to characterize the intestinal transport mechanism of SMM by the Caco-2 cells. The SMM is well known to provide therapeutic activity in peptic ulcers. The amount of SMM from various Brassicaceae family vegetables ranged from 89.08 ± 1.68 µg/g to 535.98 ± 4.85 µg/g of dry weight by using validated ultra-performance liquid chromatography-electrospray ionization-mass spectrometry method. For elucidating intestinal transport mechanism, the cells were incubated with or without transport inhibitors, energy source, or a metabolic inhibitor. Phloridzin and verapamil as inhibitors of sodium glucose transport protein (SGLT1) and P-glycoprotein, respectively, were not responsible for cellular uptake of SMM. Glucose and sodium azide were not affected by the cellular accumulation of SMM. The efflux ratio of SMM was 0.26, implying that it is not effluxed through Caco-2 cells. The apparent coefficient permeability (Papp ) of SMM was 4.69 × 10-5 cm/s, indicating that it will show good oral absorption in in vivo.


Asunto(s)
Mucosa Intestinal/metabolismo , Verduras/metabolismo , Vitamina U/química , Subfamilia B de Transportador de Casetes de Unión a ATP/metabolismo , Transporte Biológico , Brassicaceae , Células CACO-2 , Cromatografía Líquida de Alta Presión , Cromatografía Liquida , Glucosa/química , Humanos , Absorción Intestinal , Límite de Detección , Espectrometría de Masas , Úlcera Péptica/metabolismo , Permeabilidad , Reproducibilidad de los Resultados , Azida Sódica/química , Transportador 1 de Sodio-Glucosa/metabolismo , Espectrometría de Masa por Ionización de Electrospray
6.
J Biomed Res ; 30(6): 517-524, 2016 11.
Artículo en Inglés | MEDLINE | ID: mdl-27760890

RESUMEN

Leucocytozoonosis was found in three layer farms in chickens with suspected fatty liver or fatty liver hemorrhagic syndrome in Korea between 2009 and 2011. These layer chicken flocks showed both mortality and decreased egg production for one or two weeks when they were between 59 and 82 weeks old. At the necropsy, the most prominent gross lesions were found in the liver, which was enlarged, had a fragile texture, exhibited yellowish discolorations, and had various hemorrhagic lesions. Tissue reactions associated with megaloschizonts specific for Leucocytozoon caulleryi were prominent upon microscopic examination of the liver without significant lipidosis. In addition, the ovaries and uterus were the most affected organs for Leucocytozoon caulleryi multiplication, which led to decreased egg productions. Molecular studies with formalin-fixed, paraffin-embedded tissues were performed in search of a partial region of the cytochrome b gene for hemosporidian parasites. Based on these results, the causal agent was determined to be closely related to Leucocytozoon caulleryi reported in Japan and Malaysia. In this study, we describe recently re-occurring leucocytozoonosis in layer chickens, which required histopathology for disease diagnosis. To prevent outbreaks and maintain chicken health and egg production, layer chickens need to be monitored for symptoms of leucocytozoonosis.

7.
J Vet Sci ; 17(3): 323-30, 2016 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-26726018

RESUMEN

Infectious coryza (IC) is an infectious disease caused by Avibacterium (Av.) paragallinarum. IC is known to cause economic losses in the poultry industry via decreased egg production in layers. Between 2012 and 2013, Av. paragallinarum was isolated from seven chicken farms by Chungbuk National University. We identified Av. paragallinarum, the causative pathogen of IC by polymerase chain reaction (PCR) and serovar serotype A, by multiplex PCR. Antibiotic sensitivity tests indicated that a few field-isolated strains showed susceptibility to erythromycin, gentamicin, lincomycin, neomycin, oxytetracycline, spectinomycin, and tylosin. A serological survey was conducted to evaluate the number of flocks that were positive for Av. paragallinarum by utilizing a HI test to determine the existence of serovar A. Serological surveys revealed high positivity rates of 86.4% in 2009, 78.9% in 2010, 70.0% in 2011, and 69.6% in 2012. We also challenged specific pathogen-free chickens with isolated domestic strains, ADL121286 and ADL121500, according to the measured efficacy of the commercial IC vaccine, PoulShot Coryza. We confirmed the effectiveness of the vaccine based on relief of clinical signs and a decreased re-isolation rate of ADL121500 strain. Our results indicate IC is currently prevalent in Korea, and that the commercial vaccine is effective at protecting against field strains.


Asunto(s)
Pollos , Infecciones por Haemophilus/veterinaria , Haemophilus paragallinarum/fisiología , Enfermedades de las Aves de Corral/epidemiología , Vacunas Virales/farmacología , Animales , Infecciones por Haemophilus/epidemiología , Infecciones por Haemophilus/prevención & control , Infecciones por Haemophilus/virología , Haemophilus paragallinarum/genética , Haemophilus paragallinarum/inmunología , Reacción en Cadena de la Polimerasa/veterinaria , Enfermedades de las Aves de Corral/prevención & control , Enfermedades de las Aves de Corral/virología , República de Corea/epidemiología , Análisis de Secuencia de ADN/veterinaria , Organismos Libres de Patógenos Específicos
8.
Int J Anal Chem ; 2015: 650927, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25873970

RESUMEN

The approach of two different ionization techniques including electrospray ionization (ESI) and atmospheric pressure chemical ionization (APCI) coupled with liquid chromatography-tandem mass spectrometry (LC-MS/MS) was tested for the analysis of cholesteryl esters (CEs). The retention time (RT), signal intensity, protonated ion, and product ion of CEs were compared between ESI and APCI. RT of CEs from both ionizations decreased with increasing double bonds, while it increased with longer carbon chain length. The ESI process generated strong signal intensity of precursor ions corresponding to [M+Na](+) and [M+NH4](+) regardless of the number of carbon chains and double bonds in CEs. On the other hand, the APCI process produced a protonated ion of CEs [M+H](+) with a weak signal intensity, and it is selectively sensitive to detect precursor ions of CEs with unsaturated fatty acids. The ESI technique proved to be effective in ionizing more kinds of CEs than the APCI technique.

9.
Avian Pathol ; 44(1): 28-34, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25510852

RESUMEN

Chicken parvovirus (ChPV) is one of the causative agents of viral enteritis. Recently, the genome of the ABU-P1 strain of ChPV was fully sequenced and determined to have a distinct genomic composition compared with that of vertebrate parvoviruses. However, no comparative sequence analysis of coding regions of ChPVs was possible because of the lack of other sequence information. In this study, we obtained the nucleotide sequences of all genomic coding regions of three ChPVs by polymerase chain reaction using 13 primer sets, and deduced the amino acid sequences from the nucleotide sequences. The non-structural protein 1 (NS1) gene of the three ChPVs showed 95.0 to 95.5% nucleotide sequence identity and 96.5 to 98.1% amino acid sequence identity to those of NS1 from the ABU-P1 strain, respectively, and even higher nucleotide and amino acid similarities to one another. The viral proteins (VP) gene was more divergent between the three ChPV Korean strains and ABU-P1, with 88.1 to 88.3% nucleotide identity and 93.0% amino acid identity. Analysis of the putative tertiary structure of the ChPV VP2 protein showed that variable regions with less than 80% nucleotide similarity between the three Korean strains and ABU-P1 occurred in large loops of the VP2 protein believed to be involved in antigenicity, pathogenicity, and tissue tropism in other parvoviruses. Based on our analysis of full-length coding sequences, we discovered greater variation in ChPV strains than reported previously, especially in partial regions of the VP2 protein.


Asunto(s)
Pollos/virología , Variación Genética , Parvovirus/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Cartilla de ADN/genética , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa/veterinaria , Análisis de Secuencia de ADN/veterinaria , Homología de Secuencia , Especificidad de la Especie
10.
J Vet Sci ; 15(4): 579-82, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24962418

RESUMEN

Eggs exhibiting eggshell apex abnormalities (EAA) were evaluated for changes in shell characteristics such as strength, thickness, and ultrastructure. Mycoplasma synoviae (MS) infection was confirmed by serological assay along with isolation of MS from the trachea and oviduct. Changes in eggshell quality were shown to be statistically significant (p < 0.01). We also identified ultrastructural changes in the mammillary knob layer by Scanning Electron Microscopy. While eggs may seem to be structurally sound, ultrastructural evaluation showed that affected eggs do not regain their former quality. In our knowledge, this is the first report describing the occurrence of EAA in Korea.


Asunto(s)
Cáscara de Huevo/ultraestructura , Infecciones por Mycoplasma/veterinaria , Mycoplasma synoviae/fisiología , Enfermedades de las Aves de Corral/microbiología , Animales , Pollos , Cáscara de Huevo/microbiología , Microscopía Electrónica de Rastreo/veterinaria , Infecciones por Mycoplasma/microbiología , República de Corea
11.
J Sci Food Agric ; 94(1): 109-12, 2014 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-23633413

RESUMEN

BACKGROUND: Sulfur-methyl-L-methionine (SMM) has been known to provide various biological functions such as radical scavenging effect, inhibition of adipocyte differentiation, and prevention of gastric mucosal damage. Kimchi cabbages are known to be a major food source providing SMM but its bioaccessibility has not been studied. The objective of current study was to determine both the digestive stability of SMM and the amount released from Kimchi cabbages under a simulated in vitro digestion model system. RESULTS: The in vitro digestion model system simulating a human gastrointestinal tract was carried out for measuring digestive recovery and bioaccessibility of SMM. SMM was quantified by using high-performance liquid chromatography with a fluorescence detector. Recovery of an SMM standard after digestion was 0.68 and 0.65% for fasted and fed conditions, respectively, indicating that the digestive stability of the SMM standard was not affected by dietary energy or co-ingested food matrix. The SMM standard was also significantly stable in acidic pH (P < 0.05). The bioaccessibility of SMM from Kimchi cabbages was measured under a fasted condition, resulted in 8.83, 14.71 and 10.88%, for salivary, gastric and small intestinal phases, respectively. CONCLUSION: Results from our study suggest that SMM from Kimchi cabbages, a component of food sources, is more bioavailable than SMM by itself.


Asunto(s)
Brassica/química , Digestión , Compuestos de Azufre/farmacocinética , Vitamina U/farmacocinética , Disponibilidad Biológica , Cromatografía Líquida de Alta Presión , Estabilidad de Medicamentos , Ayuno , Fermentación , Humanos , Concentración de Iones de Hidrógeno , Técnicas In Vitro , República de Corea , Compuestos de Azufre/metabolismo , Vitamina U/metabolismo
12.
Poult Sci ; 92(9): 2290-8, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23960111

RESUMEN

Infectious bronchitis virus (IBV) replicates primarily in the respiratory tract and grows in various organs in chickens, with or without pathological effects. The diversity of this virus has been verified by sequence analysis of the S1 glycoprotein gene, but this method must be supplemented with further analysis for characterization of the agent. To increase our understanding of the pathogenesis of the disease caused by this virus, we investigated the response of chickens to 2 IBV with different genotypes, KIIa and ChVI. The clinical signs induced by the viruses were observed. In addition, the mRNA levels of the pro-inflammatory cytokines, IL-6, IL-1ß, and lipopolysaccharide-induced tumor necrosis factor-α factor and the serum levels of α1-acid glycoprotein, which is a major acute phase protein, were measured. The KIIa genotype (Kr/ADL110002/2011) induced clinical signs accompanied by the excessive production of pro-inflammatory cytokines and a higher viral load. In chickens infected with this isolate, simultaneous peaks in the viral copy number and cytokine production were observed at 7 dpi in the trachea and 9 d postinoculation in the kidney. On the other hand, the chickens infected with the ChVI genotype (Kr/ADL120003/2012) did not show a response other than a mild upregulation of cytokines at 1 d postinoculation, which appears to indicate the invasion of the virus. In summary, we confirmed a differential innate response following infection with distinct IBV. We hypothesize that an excessive innate response contributes to the scale of the pathophysiologic effect in chickens.


Asunto(s)
Pollos , Infecciones por Coronavirus/veterinaria , Citocinas/genética , Inmunidad Innata , Virus de la Bronquitis Infecciosa/patogenicidad , Enfermedades de las Aves de Corral/inmunología , Animales , Infecciones por Coronavirus/inmunología , Infecciones por Coronavirus/prevención & control , Citocinas/metabolismo , ADN Complementario/análisis , Ensayo de Inmunoadsorción Enzimática/veterinaria , Virus de la Bronquitis Infecciosa/genética , Interleucina-1alfa/genética , Interleucina-1alfa/metabolismo , Interleucina-6/genética , Interleucina-6/metabolismo , Riñón/virología , Orosomucoide/genética , Orosomucoide/metabolismo , Reacción en Cadena de la Polimerasa/veterinaria , Enfermedades de las Aves de Corral/prevención & control , ARN Mensajero/análisis , Análisis de Secuencia de ADN/veterinaria , Tráquea/virología , Factor de Necrosis Tumoral alfa/genética , Factor de Necrosis Tumoral alfa/metabolismo , Virulencia
13.
J Vet Sci ; 14(2): 231-3, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23814478

RESUMEN

A molecular study of intestinal samples from 21 broiler flocks with a history of enteritis revealed that 23.8% and 14.3% were positive for chicken astrovirus (CAstV) and avian rotavirus (ARV), respectively. CAstV and group A ARV were simultaneously detected in only one broiler flock. Birds in this group developed the significant intestinal lesions characterized by frothy contents, paleness, and thin intestinal walls. In this report we present an unusual case of runting stunting syndrome (RSS) with a history of high mortality and growth retardation in broiler chickens. We also make the first identification of CAstV and group A ARV in broiler chickens in Korea.


Asunto(s)
Infecciones por Astroviridae/veterinaria , Avastrovirus/genética , Pollos , Enfermedades de las Aves de Corral/diagnóstico , Infecciones por Rotavirus/veterinaria , Rotavirus/genética , Animales , Infecciones por Astroviridae/diagnóstico , Infecciones por Astroviridae/epidemiología , Infecciones por Astroviridae/virología , Avastrovirus/clasificación , Avastrovirus/aislamiento & purificación , Avastrovirus/metabolismo , Pollos/crecimiento & desarrollo , Enteritis/diagnóstico , Enteritis/patología , Enteritis/veterinaria , Enteritis/virología , Intestinos/patología , Intestinos/virología , Datos de Secuencia Molecular , Filogenia , Enfermedades de las Aves de Corral/epidemiología , Enfermedades de las Aves de Corral/virología , República de Corea/epidemiología , Rotavirus/clasificación , Rotavirus/aislamiento & purificación , Rotavirus/metabolismo , Infecciones por Rotavirus/diagnóstico , Infecciones por Rotavirus/epidemiología , Infecciones por Rotavirus/virología
14.
Chem Asian J ; 3(5): 862-7, 2008 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-18386267

RESUMEN

We report the preparation of mesoporous titania thin films with the R$\bar 3$m pore structure derived from the Im$\bar 3$m self-assembled ordering of the titania species and an EO(106)PO(70)EO(106) triblock copolymer. The films were spin-cast and then aged at 18 degrees C at a relative humidity of 70 %, which led to the orientation of the Im$\bar 3$m structure with the [111] direction perpendicular to the substrates. The [111] body-diagonal channels became vertical channels upon calcination at 400 degrees C, thus leading to thin films with vertical channels. The pores are ordered over a large area of up to 1 mum(2). The titania films can be formed on various types of substrates. By using a titania film formed on a Pt-coated Si wafer as a template, we produced by an electrochemical-deposition technique arrays of gold nanowires, whose morphology suggests that most of the pores of the titania thin films are accessible. The pore structure of vertical channels is stable up to 600 degrees C, at which temperature the wall materials crystallize into anatase.

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